Antibiotic A-32390 factor A and the tetra(C.sub.2 -C.sub.4)-acyl ester derivatives of A-32390 factor A are described in a copending U.S. application of Gary G. Marconi and Marvin W. Hoehn, titled ANTIBIOTIC A-32390 AND PROCESS FOR PREPARATION THEREOF, Ser. No. 597,112, filed this even date herewith.
Polyvinylpyrrolidone (PVP) is a polymer which has unusual complexing and colloidal properties and is generally physiologically inert. PVP has a wide variety of uses. It has been used in pharmaceuticals, cosmetics and toiletries, textiles, detergents, beverages, pigments, automotive products, plastics, and as a plasma extender. PVP has been used in pharmaceuticals as a suspending agent, as a tablet binder and/or coating agent in layered tablets and in timed-release capsules, to stabilize vitamins and aspirin tablets, and to reduce drug irritation in ophthalmic and topical preparations. The stable complex which PVP forms with iodine has been used as a germicidal preparation. PVP has also been used to increase the solubility of aromatic compounds including several useful drugs. For example, U.S. Pat. No. 3,673,163, described a co-precipitate of acronycine with PVP which provided an acronycine dosage form having increased solubility. PVP has also been used with 1-hydroxy-3-(1',1'-dimethylheptyl)-6,6-dimethyl-6,6a,7,8, 10,10a-hexahydro-9H-dibenzo[b,d]pyran-9-one) in order to enhance and retain the absorption characteristics of this drug over a prolonged period of time. When PVP has been used in combination with an antibiotic, the PVP has either been used as a binding agent (See U.S. Pat. No. 3,577,514), to sustain the release of the antibiotic (See U.S. Pat. No. 3,485,914 and U.S. Pat. No. 3,499,959) or to make the antibiotic more soluble (See U.S. Pat. No. 3,674,859). No compositions containing PVP and an antibiotic with a chemical structure resembling that of A-32390 factor A are known.